Coal Ash Basics

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What is coal ash?

Regulations

EPA published regulations in December 2014 to address the risks from the disposal of the wastes generated by electric utilities and independent power producers.

EPA proposed regulations in June 2013 that would strengthen the existing controls on discharges from steam electric power plants.

Coal ash, also referred to as coal combustion residuals or CCRs, is produced primarily from the burning of coal in coal-fired power plants. Coal ash includes a number of by-products produced from burning coal, including:

Fly Ash, a very fine, powdery material composed mostly of silica made from the burning of finely ground coal in a boiler.

Bottom Ash, a coarse, angular ash particle that is too large to be carried up into the smoke stacks so it forms in the bottom of the coal furnace.

Boiler Slag, molten bottom ash from slag tap and cyclone type furnaces that turns into pellets that have a smooth glassy appearance after it is cooled with water.

Flue Gas Desulfurization Material, a material leftover from the process of reducing sulfur dioxide emissions from a coal-fired boiler that can be a wet sludge consisting of calcium sulfite or calcium sulfate or a dry powered material that is a mixture of sulfites and sulfates.

How much coal ash is there?

Coal ash is one of the largest types of industrial waste generated in the United States. According to the American Coal Ash Association's Coal Combustion Product Production & Use Survey Report, nearly 130 million tons of coal ash was generated in 2014.

Why does EPA regulate coal ash?

The need for federal action to help ensure protective coal ash disposal was highlighted by large spills near Kingston, TN and Eden, NC which caused widespread environmental and economic damage to nearby waterways and properties.

To address the risks from improper disposal and discharge of coal ash, EPA has established national rules for coal ash disposal and is strengthening existing controls on water discharges. For more information, visit the following Web pages.